Merge the javanano map test into the main test target.

javanano/pom.xml

@@ -94,10 +94,6 @@
                   <arg value="src/test/java/com/google/protobuf/nano/unittest_multiple_nameclash_nano.proto" />
                   <arg value="src/test/java/com/google/protobuf/nano/unittest_enum_class_nano.proto" />
                   <arg value="src/test/java/com/google/protobuf/nano/unittest_repeated_merge_nano.proto" />
-                </exec>
-                <exec executable="../src/protoc">
-                  <arg value="--javanano_out=generate_equals=true:target/generated-test-sources" />
-                  <arg value="--proto_path=src/test/java/com" />
                   <arg value="src/test/java/com/google/protobuf/nano/map_test.proto" />
                 </exec>
                 <exec executable="../src/protoc">